A measurement of party efficiency that uses the amount of time a party has been together, and the amount of Experience Points gained in that time, to project an 'average' amount of Experience Point gain over time. The calculation is fairly simple, but can be deviated from in alot of ways. For example: Paladin X is 200 Experience Points into level 57 before the party begins. After 87 minutes, he is 6839 Experience Points into level 57. His exp per hour could be calculated as such: The Experience Points Per Hour is approximately 4609. * 6600 / 1.5 = 4400 or even more simply (and most commonly)